Locke insulator for 100,000 volts

Locke Porcelain Insulators.—With reference to the article in a recent issue on porcelain insulators for 100,000 volts, we are informed that a contract has been placed with the makers for "150 miles of insulators," with the option of 150 miles additional, or a total of 20,000 insulators of style No. 273; these units will be used five in series to make a single 100,000-volt insulator, to be suspended under the cross-arm, bringing the transmission wire approximately 45 in. below the latter. This contract was placed by Messrs. Sanderson & Porter, engineers, New York City, for the Union Construction Co., which is building the line for the Stanislaus Electric Power Co., of California, the first 100,000-volt line in the world.

The five units in series will test, under a rain of 1 in. in five minutes, directed at 45°, 275,000 volts, and stand a tension of 15,000 lb. maximum. The copper will be No. 00 stranded, hemp core, and will be carried on steel towers averaging 50 ft. high.

During the preliminary investigations scores of different sizes and combinations of parts were tested, and several hundred pieces came under electrical tests of the most severe nature, and in all this testing not one piece of porcelain was punctured or proved defective in any manner.

A contract for 100,000-volt insulators for the Great Western Power Co., California (Viele, Blackwell & Buck, engineers, New York), for 10,000 of the same units as used for the Stanislaus job, has also been secured by the company, whose agents in this country are MESSRS. GEIPEL & LANGE.